Lina Medina’s parents were worried. Lina, one of nine children in this poor family of the Peruvian Andes, had a seemingly inexplicable abdominal growth — which was growing larger by the week.

Fearing she had cancer, Lina’s parents brought her to the doctor. The Peruvian girl was cancer-free; she was, however, seven months pregnant.

Six weeks later, on May 14, 1939, Lina gave birth via Cesarean section to baby Gerardo, who weighed six pounds at birth.

Lina Medina youngest confirmed mother

Lina was five years, seven months, and 21 days old at the time of Gerardo’s birth — the youngest mother on record.

In performing the c-section, doctors noted that Lina had gone through puberty at a very early age, called “precocious puberty.” Researchers further pieced together shocking details of Lina’s ascent into “adulthood”: she had developed mature breasts by age four and had her first menstrual cycle at two and a half (with some reports suggesting that her first period came at the age of eight months).

She’s never revealed the identity of Gerardo’s father — and, in fact, may not know who it is; the doctor who delivered Gerardo noted that Lina’s mastery of the details of her pregnancy was fleeting, due in part to her young age. But the pregnancy was definitely real.

Pregnant Lina Medina

One photograph of the pregnant five year old exists (available here) and scores of evidence — x-rays, doctors notes, biopsies, etc. — exist proving the pregnancy and delivery to be true. After she gave birth, she appeared in a photo with her doctor and son, seen above.

Lina and her parents ended up raising Gerardo. Until he was ten Gerardo believed she was his older sister, but around that age he was informed that Lina was, in fact, her mother. For her part, Lina is otherwise healthy and still alive today, albeit in incredibly poor conditions. She married later in life and, in 1972, had another son. Gerardo died in 1979, at age 40, of a bone marrow disease unrelated to his mother’s age at his birth.